Threadless couplings have been developed to simplify and speed the installation of piping systems such as building sprinkler systems. Thread and bayonet-type couplings require relative turning movement between the system components which complicates installation and repair of those components. In addition, forming the threads on the pipe or providing the bayonet connection on the pipe is time consuming and adds to the cost of the installation.
U.S. Pat. No. 4,165,892 granted Aug. 28, 1979 to Edward Piatek and Timothy Brady for "Coupling for Releasibly Securing One End of a Rod-like Member" discloses one form of threadless coupling which has enjoyed some commercial success. This coupling is sold by Victaulic Company of America, South Plainfield, N.J.
The Victaulic brand couplings work well with conventional Schedule 10 and Schedule 40 plain end steel pipe. However, because of the cost of the couplings the overwell system costs can sometimes exceed the cost of systems utilizing more conventional threaded couplings.
There remains a need for a light weight, thinner walled and less expensive pipe to improve the competitiveness and performance of systems utilizing the Victaulic brand couplings.